湖南省大通湖百余年环境演化历史及营养物基准的建立  

ENVIRONMENTAL EVOLUTION OF DATONG LAKE OVER THE PAST 160 YEARS AND ITS NUTRIENT BASELINE

作　　者：廖粤军 李春华[2] 董旭辉 魏伟伟[2] LIAO Yue-Jun;LI Chun-Hua;DONG Xu-Hui;WEI Wei-Wei(School of Geography and Remote Sensing,Guangzhou University,Guangzhou 510006,China;National Engineering Laboratory for Lake Pollution Control and Ecological Restoration,State Environmental Protection Key Laboratory for Lake Pollution Control,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;Centre for Climate and Environmental Changes,Guangzhou University,Guangzhou 510006,China)

机构地区：[1]广州大学地理科学与遥感学院,广州510006 [2]湖泊水污染治理与生态修复技术国家工程实验室,国家环境保护湖泊污染控制重点实验室,中国环境科学研究院,北京100012 [3]广州大学气候与环境变化研究中心,广州510006

出　　处：《水生生物学报》2021年第1期206-215,共10页Acta Hydrobiologica Sinica

基　　金：国家水体污染控制与治理科技重大专项(2012ZX07101-009);国家自然科学基金(41901222)资助。

摘　　要：科学有效地治理退化湖泊需要知晓湖泊的演化历史,并设立合理的参照目标(即环境基准)来及时评判治理效果。湖南省大通湖位于经济发达的长江中下游地区,发挥着重要的湖泊水生态系统服务功能。在强烈的人类活动干扰下,该湖近年来生态系统退化严重,但其水环境演变的历史缺少详细的记录。研究对大通湖沉积钻孔的年代、烧失量、化学元素、沉积物总磷(TP)和沉积硅藻等沉积指标进行了分析,重建了大通湖百余年来的环境变化历史。结果表明:在人类干扰加强和气候变化的共同作用下,大通湖生态系统及环境发生了显著的变化,硅藻群落由中营养属种Aulacoseira granulata占优过渡到以富营养浮游类型Stephanodiscus hantzschii、S.minutulus占优的过程,揭示了该湖自1980s以来显著的富营养化过程;对应的,其他沉积指标亦发生了显著的变化。冗余分析揭示出沉积物总磷(TP)和铅(Pb)含量是影响湖泊环境演化的2个显著变量,这表明工农业发展带来的营养和重金属输入对大通湖环境演化影响巨大。利用区域-总磷转换函数重建了大通湖过去百余年湖水总磷变化历史,选择1850s人类活动相对较弱时期的湖水总磷(50—60μg/L)及沉积物磷的浓度(600 mg/kg)值作为该湖的基准环境,为湖泊的富营养化治理提供修复目标。Shallow lakes are essential part of aquatic ecosystem and play irreplaceable roles in regional water supply,shipping transportation,maintaining regional ecosystem balance and other aspect.However,most of Chinese shallow lakes are facing environmental problems,especially the eutrophication.The restoration and management of eutrophic lakes require knowledge of their environmental evolution and nutrient baseline.Such knowledge is crucial for sustainable environment management and decision-making.Datong Lake is the biggest inland aquaculture lake in Hunan Province which locates in one of the developed regions of China(in the middle and lower reaches of the Yangtze River).Under the strong disturbance of human activities(i.e.agriculture,industrialization,urbanization),the lake ecosystem has deteriorated during recent years.Due to the limited information on the history of water environment,we lack of the information of the Datong Lake’s nutrient baseline,leading to a restoration dilemma that could not provide a scientific target for the system governance.Paleoliminological technique is important for assessing the lake’s historical evolution,nutrient baseline and degradation mechanism.Among the multiple paleolimnological proxies,diatom plays a primary product role in lacustrine ecosystems and responds sensitively to external and internal drivers.Diatom remain can be well preserved and becomes one of potential proxy indicators of lake ecosystem changes.Based on the multiple proxy analysis including 210Pb/137Cs,loss-on-ignition,metal elements,sediment total phosphorus(TP),and diatoms from Datong Lake,we reconstructed the history of local environment over the past 160 years.With the increasing pressure from human disturbance and climate change,diatom communities had experienced a significant shift from mesotrophic specie Aulacoseira granulata to eutrophic planktonic species Stephanodiscus hantzschii,S.minutulus,underlin-ing the process of eutrophication.Diatom inferred-total phosphorous(DI-TP)started around 1980 with TP

关 键 词：大通湖 环境演化 硅藻 总磷 营养物基准 

分 类 号：S932.2[农业科学—渔业资源]